const timer = setInterval(function() {
  const ele = document.getElementById('content_right');
  if(ele.style.display!=="none"){
    ele.style="display:none";
    clearInterval(timer);
  }
}, 50)


document.getElementById('form').onclick=function() {
  const timer = setInterval(function() {
    const ele = document.getElementById('content_right');
    if(ele.style.display!=="none"){
      ele.style="display:none";
      clearInterval(timer);
    }
  }, 50)
}